What are Immune-Based Therapies?

AIDS researchers have primarily concentrated on finding drugs that prevent HIV from replicating (creating more virus) inside the body. These drugs are often referred to as "antivirals". More recently, many researchers have been trying to find ways to help a person's immune system fight the virus on its own. Called "immune-based therapies", some of these treatments are now being studied in large clinical trials.

One approach is to reproduce important proteins, called "cytokines", that help regulate a person's immune system, then use them to stimulate or inhibit the growth and activity of various immune system cells. The most tested treatment using this approach is Proleukin®, a high-tech recreation of interleukin-2 (IL-2), a naturally occurring cytokine that stimulates the production of T-cells. There is also BAY 50-4798, a modified version of IL-2. It is hoped that this modification will allow BAY 50-4798 to stimulate T-cell production with fewer of the side effects often seen in patients receiving IL-2 therapy. Another cytokine that is in the early stages of development is IL-12.

Another approach is the use of "therapeutic vaccines". While traditional vaccines are used to "prime" a person's immune system before a possible infection occurs, therapeutic vaccines attempt to "teach" a person's immune system to fight a virus long after it has infected them. One such candidate is IR103, which contains the therapeutic vaccine Remune® and the adjuvant Amplivax™, an immune system stimulant used to boost the body's immune response to Remune and HIV.

Certain hormones have also been shown to protect and boost key immune system cells that can be damaged by HIV. Immunitin™ is similar to the naturally occurring hormone DHEA and is currently being studied as a immune-based therapy. There is also a possibility that Serostim® (human growth hormone), a medication approved for the treatment of wasting syndrome and currently being studied for the treatment of lipodystrophy, may help the thymus gland produce new T-cells.

While these and other immune-based therapies are being intensively researched, it is important to note that no studies have yet been completed that have proven a clinical benefit (the ability to prolong a person's life).